Retinoscope.



PATENTED OCT 15, 1907. S. G. THOMSON.

RETINOSGOPE. APPLICATION 11,111) 001*.20. 1000.

2 sums-sum 1.

THE N No. 868,373. PATENT ED OCT. 15, 1907.

S. G. THOMSON.

. .RETINOSGOPE. APPLIOAITION nun 001'. 20. 1906.

2 SH'EETS-SHEET 2'.

3mm: 63 6, 7&072/50 27- Tn: NORRIS PETERS cm, vmsumcwrv. n. c

STEWART O. THOMSON, OF ARROWSMITH, ILLINOIS.

RETINOSCOPE. t

Specification of Letters Patent.

Patented Oct. 15, 1907.

Application filed October 20, 1906. Serial No. 339,847.

To (ll Z whom it may concern:

Be it known that I, STEWART C. THOMSON, a citizen of the United States,residing at Arrowsmith, in the county of McLean and State of Illinois,have invented certain new and useful Improvements in Retinoscopes, ofwhich the following is a specification.

This invention provides an instrument for determining errors inrefraction by skiascopy and which will obviate the necessity for a darkroom and which may be used by the average practitioner, the instrument.being adapted to be readily reduced in size for convenience of storingand handling and admitting of its use in much the same manner as anophthalmoscope and whether the patient is sitting or in a recumbentposition. I

For a full description of the invention and also to acquire a knowledgeof the details of construction reference is to be had to the followingdescription and accompanying drawings.

While the invention may be adapted to different forms and conditions bychanges in the structure and minor details without departing from thespirit or essential features thereof, still the preferred embodiment isshown in the accompanying drawings, in which:

Figure l is a perspective view of a retinoscope embodying the invention.Fig. 2 is a detail view of the cap or end piece receiving the serieslens holder. Fig. 3 is a detail view of the end of the telescoping tubeadapted to receive the ordinary hand retinoscope. Fig. 4 is a horizontalsection of the larger end portions of the telescoping tube. Fig. 5 is afront view of a portion of the series lens holder. Fig. 6 is alongitudinal section of the series lens holder.

Corresponding and like parts are referred to in the followingdescription and indicated in all the views of the drawings by the samereference characters The instrument comprises a telescoping tube 1 ofsuch formation as to admit of its sections being readily moved eitherinward or outward, as may be desired. The larger end of the telescopingtube is provided with supports 2 adapted to receive and hold in place anordinary hand retinoscope 3. A cap or end piece 4 is fitted to the smallend of the telescoping tube by means of a slip joint and is provided atits outer end with guides 5, which receive lens holder 6 for a se ricsof test lenses. the said holder being vertically adjustable in theguides 5 and adapted to receive a number of lenses selected from a caseand arranged in the holder one above the other. The telescoping tube isadapted to be supported by means of a suitable stand which comprises abase 7 and an upright S, the latter being tubular and receiving a stem 9to which is attached a band 10, the latter embracing the telescopingtube 1. The stem 9 is adjustable in the upright S and is held in anadjusted position by means of a set screw threaded into a side of theupright 8.

An inclined tube 11 is fitted to a side of the telescoping tube near itsouter end and inclines so as to occupy a rearward and outward anglingposition When the telescoping tube ,1 is placed in an approximatelyhorizontal position. A second tube 12 is connected to the outer end ofthe inclined tube 11 and is arranged to occupy a perpendicular positionand is adapted to receive a suitable light or illuminator and a screenthe latter being provided with a series of openings so as to regulatethe amount of light thrownupon the retinoscope 3. The inclined tube 11is so positioned as to direct the light from the illuminator upon theretinoscope 3 by means of which the beam of light is directed to thetelescoping tube 1 into the eye of the patient to enable any error ofrefraction being ascertained.

The series lens holder 6 consists of a strip of metal having openings atintervals in its length and provided with flanged supports 13 at thelower side of the respective openings to receive and support the severallenses 14. The lens holder is vertically adjustable in the guides 5 ofthe end piece 4 and in order that the operator may be enabled to readilyadjust the lens holder from the outer end of the telescoping tube 1, arod 15 is provided and is connected at one end to the lower end of thelens holder 6.

A forked bar 16 is secured to the upright 8 of the stand and projectsupwardly therefrom and the rod 15 is supported by one member of the barand is adapted to take underneath any one of a series of notches orprojections 16 on the other member, whereby to hold the part 6 at thedesired adjustment.

The screen for regulating the light to the hand retinoscope ispreferably in the form of a band 17 which encircles the vertical tube 12and operates through slots formed in opposite sides of the inclined tube11.

Having thus described the invention, what is claimed as new is:

1. In a retinoscope, a tube adapted to have light directed therethroughfrom an illuminator by means of a lens, a cap fitted to said tube andprovided with guides, a lens holder" adjustable in the guides of saidcap, a jointed rod connected with said lens holder, and a notched bar cooperating with the rod for holding it and the lens holder in an adjustedposition.

2. In an instrument of the character specified, the combination of amain tube adapted to receive a retinoscope at one end and lenses at theopposite end, and an adjustable holder for said lenses, :1 stand forsupporting said tube and adjustable to admit of regulating the elevationof the instrument, a rod extended from the adjustable lens holder and anotched bar projected from the stand and cooperating with the rod tohold it and the lens holder in an adjusted position.

3. An instrument of the character described, comprising a tube adaptedto receive a retinoscope at one end and provided with guides at theopposite end, a lens holder vertically adjustable within said guides andprovided with a series of openings at intervals and lens supportscontiguous to the respective openings, a stand upon which said tube issupported and adjustably mounted so as to be held at diiferentelevations, and a supporting device secured to the lens holder andadjustably mounted upon the stand 4. An instrument of the characterspecified, comprising a main tube adapted to receive a retinoscope atone end, a lens holder adapted to be applied to the opposite end of 10the tube and arranged to support a series of test lenses, :1

stand on which said tube is mounted, a forked bar se 1 'cured to saidstand, one member of said bar being pro vided with a series of notches,and a rod connected to the lens holder and to one member of the fork andadapted to take under any one of the notches of the other member, as andfor the purpose set forth.

In testimony whereof I afiix my signature in presence of two Witnesses.

, STEWART C. THOMSON. [L. s.] Witnesses:

L. C. VIRGIEL,

J. H. JAcoBs.

